Here’s a very simple method: when you set out to make something, whether it be software or policies or mechanisms for organizing information, ask yourself what’s the worst that could happen. Imagine a powerful person, someone endowed with the right circumstances of birth such that the odds are nearly always in their favor; and imagine, also, the reverse—someone for whom discrimination, oppression, violence, and poverty are commonplace. Then optimize to protect the latter, even at the expense of the former. And do it right away: not after you scale, not after the money is rolling in, not after a leak exposes you, but now. Yesterday, even. Go.